Suicide rates among cancer patients were determined from the Connectict SEER Cancer Registry and compared with age-matched Connecticut State suicide rates to estimate relative risks. Among male cancer patients a two-fold risk was found, but no excess risk was found for females. For men, a greater risk was evident the first few years after diagnosis than later. Preliminary data, only partially controlled for other variables, suggest a slightly higher risk for ever-married than for never-married patients, and a clearly higher risk for patients with metastasized tumors than for those with localized tumors. Slightly greater risk appears in surgical patients than in those treated otherwise.